ACLCacheLifetime determines the number of seconds before cache entries expire. Each time an entry in the cache is referenced, its age is calculated and checked against ACLCacheLifetime. The entry is not used if its age is greater than or equal to the ACLCacheLifetime. If this value is set to 0, the cache is turned off.
If you use a large number for this value, you may need to restart the Sun Java System Web Server when you make changes to the LDAP entries. For example, if this value is set to 120 seconds, the Sun Java System Web Server might be out of sync with the LDAP server for as long as two minutes. If your LDAP entries are not likely to change often, use a large number.